This applications claims priority to European patent application No. 00830352.1 filed May 16, 2000.
The subject of the present invention is a supporting roller.
One known type of supporting roller comprises a skirt, for supporting a return side of a chain of a conveyor, and, coaxial with the skirt, a hub designed to rotate idly on a journal.
Though in many ways satisfactory, known rollers leave much to be desired when it comes to durability of operation.
One of the main problems with known rollers is that they tend, as they rotate about their respective journals, to pick up impurities, such as particles resulting from wear, and dirt in general, which greatly increase the resistance to rotation of the supporting roller on the journal. Because of the increasing resistance to rotation present between the known roller and the journal, the return side of the chain tends to skid on the surface of the skirt, resulting in accelerated wear of the parts in contact with each other.
Another problem with known rollers, especially under the conditions of use at high speeds of rotation of the chain, is the noise of the coupling between the skirt and the chain.
The problem addressed by the present invention is to devise a supporting roller with structural and functional characteristics such as to overcome the abovementioned problems cited with reference to the prior art.
This problem is solved with a supporting roller of the type specified above, characterized in that a sleeve made of a material having high friction is laid over the skirt.
Specifically, the invention is a supporting roller of the type comprising a skirt, for supporting a return side of an endless chain of a chain conveyor, and, coaxial with the skirt, a hub designed to rotate idly on a journal, wherein it comprises a sleeve made of a material having high friction laid over the skirt.
The invention also provides a support for a return side of an endless conveyor chain, comprising at least two supporting rollers rotating idly side by side on a journal, wherein each roller includes a hub mounted on the journal and supporting a skirt on which is disposed a friction sleeve.